Now that kernel mode SIMD is guaranteed to be available when executing
in task or softirq context, we no longer need scalar fallbacks to use
when the NEON is unavailable. So get rid of them.
Signed-off-by: Ard Biesheuvel <[email protected]>
---
arch/arm64/crypto/ghash-ce-glue.c | 209 +++++---------------
1 file changed, 51 insertions(+), 158 deletions(-)
diff --git a/arch/arm64/crypto/ghash-ce-glue.c b/arch/arm64/crypto/ghash-ce-glue.c
index 720cd3a58da3..15794fe21a0b 100644
--- a/arch/arm64/crypto/ghash-ce-glue.c
+++ b/arch/arm64/crypto/ghash-ce-glue.c
@@ -362,84 +362,36 @@ static int gcm_encrypt(struct aead_request *req)
err = skcipher_walk_aead_encrypt(&walk, req, false);
- if (likely(crypto_simd_usable())) {
- do {
- const u8 *src = walk.src.virt.addr;
- u8 *dst = walk.dst.virt.addr;
- int nbytes = walk.nbytes;
-
- tag = (u8 *)&lengths;
-
- if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE)) {
- src = dst = memcpy(buf + sizeof(buf) - nbytes,
- src, nbytes);
- } else if (nbytes < walk.total) {
- nbytes &= ~(AES_BLOCK_SIZE - 1);
- tag = NULL;
- }
-
- kernel_neon_begin();
- pmull_gcm_encrypt(nbytes, dst, src, ctx->ghash_key.h,
- dg, iv, ctx->aes_key.key_enc, nrounds,
- tag);
- kernel_neon_end();
-
- if (unlikely(!nbytes))
- break;
-
- if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE))
- memcpy(walk.dst.virt.addr,
- buf + sizeof(buf) - nbytes, nbytes);
-
- err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
- } while (walk.nbytes);
- } else {
- while (walk.nbytes >= AES_BLOCK_SIZE) {
- int blocks = walk.nbytes / AES_BLOCK_SIZE;
- const u8 *src = walk.src.virt.addr;
- u8 *dst = walk.dst.virt.addr;
- int remaining = blocks;
-
- do {
- aes_encrypt(&ctx->aes_key, buf, iv);
- crypto_xor_cpy(dst, src, buf, AES_BLOCK_SIZE);
- crypto_inc(iv, AES_BLOCK_SIZE);
-
- dst += AES_BLOCK_SIZE;
- src += AES_BLOCK_SIZE;
- } while (--remaining > 0);
-
- ghash_do_update(blocks, dg, walk.dst.virt.addr,
- &ctx->ghash_key, NULL);
-
- err = skcipher_walk_done(&walk,
- walk.nbytes % AES_BLOCK_SIZE);
- }
-
- /* handle the tail */
- if (walk.nbytes) {
- aes_encrypt(&ctx->aes_key, buf, iv);
+ do {
+ const u8 *src = walk.src.virt.addr;
+ u8 *dst = walk.dst.virt.addr;
+ int nbytes = walk.nbytes;
- crypto_xor_cpy(walk.dst.virt.addr, walk.src.virt.addr,
- buf, walk.nbytes);
+ tag = (u8 *)&lengths;
- memcpy(buf, walk.dst.virt.addr, walk.nbytes);
- memset(buf + walk.nbytes, 0, sizeof(buf) - walk.nbytes);
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE)) {
+ src = dst = memcpy(buf + sizeof(buf) - nbytes,
+ src, nbytes);
+ } else if (nbytes < walk.total) {
+ nbytes &= ~(AES_BLOCK_SIZE - 1);
+ tag = NULL;
}
- tag = (u8 *)&lengths;
- ghash_do_update(1, dg, tag, &ctx->ghash_key,
- walk.nbytes ? buf : NULL);
+ kernel_neon_begin();
+ pmull_gcm_encrypt(nbytes, dst, src, ctx->ghash_key.h,
+ dg, iv, ctx->aes_key.key_enc, nrounds,
+ tag);
+ kernel_neon_end();
- if (walk.nbytes)
- err = skcipher_walk_done(&walk, 0);
+ if (unlikely(!nbytes))
+ break;
- put_unaligned_be64(dg[1], tag);
- put_unaligned_be64(dg[0], tag + 8);
- put_unaligned_be32(1, iv + GCM_IV_SIZE);
- aes_encrypt(&ctx->aes_key, iv, iv);
- crypto_xor(tag, iv, AES_BLOCK_SIZE);
- }
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE))
+ memcpy(walk.dst.virt.addr,
+ buf + sizeof(buf) - nbytes, nbytes);
+
+ err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
+ } while (walk.nbytes);
if (err)
return err;
@@ -464,6 +416,7 @@ static int gcm_decrypt(struct aead_request *req)
u64 dg[2] = {};
be128 lengths;
u8 *tag;
+ int ret;
int err;
lengths.a = cpu_to_be64(req->assoclen * 8);
@@ -481,101 +434,41 @@ static int gcm_decrypt(struct aead_request *req)
err = skcipher_walk_aead_decrypt(&walk, req, false);
- if (likely(crypto_simd_usable())) {
- int ret;
-
- do {
- const u8 *src = walk.src.virt.addr;
- u8 *dst = walk.dst.virt.addr;
- int nbytes = walk.nbytes;
-
- tag = (u8 *)&lengths;
-
- if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE)) {
- src = dst = memcpy(buf + sizeof(buf) - nbytes,
- src, nbytes);
- } else if (nbytes < walk.total) {
- nbytes &= ~(AES_BLOCK_SIZE - 1);
- tag = NULL;
- }
-
- kernel_neon_begin();
- ret = pmull_gcm_decrypt(nbytes, dst, src,
- ctx->ghash_key.h,
- dg, iv, ctx->aes_key.key_enc,
- nrounds, tag, otag, authsize);
- kernel_neon_end();
-
- if (unlikely(!nbytes))
- break;
-
- if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE))
- memcpy(walk.dst.virt.addr,
- buf + sizeof(buf) - nbytes, nbytes);
-
- err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
- } while (walk.nbytes);
-
- if (err)
- return err;
- if (ret)
- return -EBADMSG;
- } else {
- while (walk.nbytes >= AES_BLOCK_SIZE) {
- int blocks = walk.nbytes / AES_BLOCK_SIZE;
- const u8 *src = walk.src.virt.addr;
- u8 *dst = walk.dst.virt.addr;
-
- ghash_do_update(blocks, dg, walk.src.virt.addr,
- &ctx->ghash_key, NULL);
-
- do {
- aes_encrypt(&ctx->aes_key, buf, iv);
- crypto_xor_cpy(dst, src, buf, AES_BLOCK_SIZE);
- crypto_inc(iv, AES_BLOCK_SIZE);
-
- dst += AES_BLOCK_SIZE;
- src += AES_BLOCK_SIZE;
- } while (--blocks > 0);
+ do {
+ const u8 *src = walk.src.virt.addr;
+ u8 *dst = walk.dst.virt.addr;
+ int nbytes = walk.nbytes;
- err = skcipher_walk_done(&walk,
- walk.nbytes % AES_BLOCK_SIZE);
- }
+ tag = (u8 *)&lengths;
- /* handle the tail */
- if (walk.nbytes) {
- memcpy(buf, walk.src.virt.addr, walk.nbytes);
- memset(buf + walk.nbytes, 0, sizeof(buf) - walk.nbytes);
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE)) {
+ src = dst = memcpy(buf + sizeof(buf) - nbytes,
+ src, nbytes);
+ } else if (nbytes < walk.total) {
+ nbytes &= ~(AES_BLOCK_SIZE - 1);
+ tag = NULL;
}
- tag = (u8 *)&lengths;
- ghash_do_update(1, dg, tag, &ctx->ghash_key,
- walk.nbytes ? buf : NULL);
-
- if (walk.nbytes) {
- aes_encrypt(&ctx->aes_key, buf, iv);
+ kernel_neon_begin();
+ ret = pmull_gcm_decrypt(nbytes, dst, src, ctx->ghash_key.h,
+ dg, iv, ctx->aes_key.key_enc,
+ nrounds, tag, otag, authsize);
+ kernel_neon_end();
- crypto_xor_cpy(walk.dst.virt.addr, walk.src.virt.addr,
- buf, walk.nbytes);
+ if (unlikely(!nbytes))
+ break;
- err = skcipher_walk_done(&walk, 0);
- }
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE))
+ memcpy(walk.dst.virt.addr,
+ buf + sizeof(buf) - nbytes, nbytes);
- if (err)
- return err;
+ err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
+ } while (walk.nbytes);
- put_unaligned_be64(dg[1], tag);
- put_unaligned_be64(dg[0], tag + 8);
- put_unaligned_be32(1, iv + GCM_IV_SIZE);
- aes_encrypt(&ctx->aes_key, iv, iv);
- crypto_xor(tag, iv, AES_BLOCK_SIZE);
+ if (err)
+ return err;
- if (crypto_memneq(tag, otag, authsize)) {
- memzero_explicit(tag, AES_BLOCK_SIZE);
- return -EBADMSG;
- }
- }
- return 0;
+ return ret ? -EBADMSG : 0;
}
static struct aead_alg gcm_aes_alg = {
--
2.20.1
On Fri, May 21, 2021 at 12:20:49PM +0200, Ard Biesheuvel wrote:
> Now that kernel mode SIMD is guaranteed to be available when executing
> in task or softirq context, we no longer need scalar fallbacks to use
> when the NEON is unavailable. So get rid of them.
>
> Signed-off-by: Ard Biesheuvel <[email protected]>
> ---
> arch/arm64/crypto/ghash-ce-glue.c | 209 +++++---------------
> 1 file changed, 51 insertions(+), 158 deletions(-)
Reviewed-by: Eric Biggers <[email protected]>